✓ Effortless Math · Free Tool

Triangle Calculator

Solve a right triangle from its two legs, or a general triangle from three sides (SSS) — get all sides, all angles, the area, the perimeter, a scaled diagram, and full step-by-step working.

Right triangle:  c = √(a² + b²)  ·  SSS:  Law of Cosines + Heron
leg a leg b

For a right triangle, enter the two legs a and b — the legs meet at the right angle. All lengths must be greater than 0.

Results

Solved triangle
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Side a
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Side b
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Side c (hypotenuse)
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Angle A (opposite a)
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Angle B (opposite b)
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Angle C (opposite c)
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Area
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Perimeter
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Diagram

SidesVerticesRight angle / labels

Step-by-step